After the events of UNDERTALE's genocide route, GASTER found Chara in the depths and held them in a flipping chokehold, and after some resistance killed them for killing his entire family and kingdom, causing his LV to rocket up to Infinity. As such, he crafted a VESSEL to store this LV within, so he could make DELTARUNE in peace. This VESSEL was banished (it's not the player's vessel, don't worry) away from UNDERTALE, DELTARUNE and the depths, and sent away to a new world, one where naught existed. There they gradually bled LV until a crude world was forged, one filled with suffering. The VESSEL, now emptied to a point where it could coexist with itself (still brimming with LV though) looked onto this writhing world with pity, and so gave itself up to save the suffering land, leaving 2 children left to govern the remaining world.
The world was vast, and was split into two sections, one for the eldest child and one for the youngest. The youngest could not manage their land though, for lack of experience, so the eldest ruled the world until their sibling could inherit their land.
However, as time passed the younger sibling began to believe the elder one was restraining their rightful land from them, in order to control the whole world, them along with it — and so, when they came of age, they weaponised their land with a powerful weapon known as HATE. The elder sibling saw this, and became paranoid that the younger sibling was planning to steal their land, and so filled their lands too with HATE, leading to a vast war between the two. In the end, warlords emerged from within both their ranks and consolidated power, eventually reducing both siblings to near mortals, albeit with enhanced ability and everlasting lifespans. As time went on, however, these warlords were overthrown in revolutions, and those states waged war with each other, until 4 superstates remained, 2 for each historic domain:
Hearts and Diamonds for the elder sibling's former land,
and Clubs and Spades for the younger sibling's former land.
As for the siblings themselves, the elder one gave up on this world and confined themself to a vast library, one within a rift of space and time, where and whence they could observe all the world without issue. Within this library they studied the world and planned their return to GASTER.
The younger one, meanwhile, had been drastically injured and bled LV, reducing themself to a mere shade of their previous power. Ashamed, they took on a new name, one as fragmented as their form:
5949d5.
Oh, and new tag btw: "au".
